Zarnstorff, a principal research physicist at PPPL, and Prager, a professor of physics and director of the Madison Symmetric Torus experiment at the University of Wisconsin, are being recognized for their discovery of the "bootstrap current" in fusion plasmas. While working on the Toroidal Octupole experiment at the University of Wisconsin, Prager and his then-graduate student Zarnstorff first detected this phenomenon, in which the electrical current is generated by the plasma itself. At PPPL, Zarnstorff conducted experiments on the Tokamak Fusion Test Reactor that firmly established the existence of the bootstrap current in high-temperature, fusion-relevant plasmas.

"The work of Prager and Zarnstorff, experimentally confirming the theoretically predicted self-sustaining bootstrap current, has revolutionized the design of fusion systems, providing a route to plasmas that can themselves sustain some of the magnetic fields that confine them," said the current PPPL director, Robert Goldston.

Prager and Zarnstorff received the honor at the Nov. 17-21 APS-Division of Plasma Physics meeting. The annual award consists of $5,000 to be divided equally in the case of multiple recipients.

Pager has played a key role for decades in efforts to harness the energy potential of nuclear fusion by working with charged gases known as plasmas. He was named in July as the new director of PPPL. His appointment is expected to be effective this fall.

PPPL is one of 10 national science laboratories funded by Department of Energy's Office of Science. As the department completes a series of competitive bidding processes for the management and operations contracts for all of these labs, Princeton currently is competing for a new contract to continue managing the lab. The University has successfully managed the lab since its inception in 1951.